Methods and criteria of restoration

The restoration consists of material activity of intervention. The nature of the intervention, in that it takes place on an object of great artistic or historical value, requires that certain criteria and methods must be followed rigorously. The fundamental attitude must be of profound respect for the object. The restorer must aim to hide his own presence; the best restorations are those that appear to be the least, in such a way as to allow the work to retain its originality. Such an approach does not imply that the piece must return to its original form. The originality refers to the authenticity of its actual situation: if a piece is ancient, the passage of time must also be recognizable and the piece should not appear new.

Therefore the restoration should take place on the cause of the damage that the work has suffered and it must attempt to eliminate it or impede its progress. The restoration must find a balance between the need to respect the object, to avoid hiding its critical features while paying great attention (especially in the case of a work of art) revealing the aesthetic characteristics of the piece. This implies that it is possible to carry out discrete interventions that aid the artistic potential of the work to express itself as well as is possible. For example if there is a gap in the coloured surface or the structure of a statue it is permitted to fill the gap as long as the process is reversible, therefore eliminating future intervention. Such a process must be completed in a recognizable manner – the restored parts must be distinct from the originals. For all of the operations that are carried out on a work of art, it is opportune to use compatible substances i.e. similar or equal to the originals. Following a period when it was previously in favour, nowadays the use of synthetic substances derived from petroleum (such as acrylic resin) used to consolidate a work or protect its surface, tends to be limited.

Restoration problems

A work of art often displays two types of problem, those which relate to the structure and those that relate to its appearance and exist only superficially. The first requires delicate operations to consolidate the structure in order that the work can retain its solidity. The second type necessitates cleaning of the surface to consolidate it and the eventual integration of the painting. The characteristics of the intervention are distinguished according to the materials and the type of object involved: obviously some operations are more specific, a tapestry requires a wholly different approach to a bronze, or a marble statue or a painting. Some propose that the restoration of architecture is vastly different to the restoration of a work of art or an archaeological relic.

However, some methodologies are common to all types: each intervention requires a prior study of the work, both from a historical and material point of view; this must be carried out using scientific investigations. All interventions require an attitude of extreme caution and the objective to intervene as little as possible while still creating an effective restoration. It is also necessary to study the conditions that will maximise the conservation of the object in the future either by modifying the environment in which the piece is found or by providing the piece with adequate protection. Nowadays, the importance of maintenance is paramount, the combinations of controls and small interventions that, if carried out correctly, can in many cases extinguish the need for a serious restoration that may prove to be invasive. According to certain characteristics of an intervention the following theoretical principles must be followed: these relate mainly to ethical issues. In each case the restoration is an activity that is extremely difficult and highly sophisticated in which the fields of science and manual ability converge in order to reflect the level of civilization and culture of a people.